"The Chronic Persistent Dermatitis Mutation (cpdm) in mice is a spontaneous, autosomal recessive mutation that is characterized by the development of thickened, scaly skin similar to that observed in the human inflammatory skin condition called psoriasis. Histologically, the skin of these animals have many leukocytes in the skin including the presence of neutrophils in the epidermis. L-selectin is an adhesion molecule found on all classes of leukocytes and is thought to be important in mediating the initial attachment of leukocytes to vascular endothelium. Preliminary staining of skin sections from these mice showed easily detectable amounts of a ligand for L-selectin on the dermal endothelium of these animals. To date, this is the only genetic animal model of dermal vascular expression of L-selectin ligands in an inflammatory skin condition. It has been shown that L-selectin ligands are expressed in a variety of human inflammatory skin conditions including psoriasis. Because of this, we plan to use this model in a variety of ways to better understand the role of L-selectin and its ligands in the recruitment of leukocytes to the skin. Recent data from collaborators indicate the predominant cells in the dermal infiltrate are eosinophils. Because of the difficulties involved in studing eosinophil skin migration in mice, we have placed little emphasis on this project in the past year."